Timeline

Record a bounded history of public lifecycle events (Session Timeline / Event Timeline).

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Import path

import { createBrowserLifecycle, createTimelineApi } from "@jayoncode/browser-lifecycle";

Usage

import { createBrowserLifecycle, createTimelineApi } from "@jayoncode/browser-lifecycle";

const lifecycle = createBrowserLifecycle();
const timeline = createTimelineApi(lifecycle, { maxEvents: 200 });

timeline.events(); // structured entries
timeline.record(); // alias of events()
timeline.format(); // ["10:05:42 page:hidden", ...]

timeline.clear();
timeline.dispose();

Rules

• maxEvents is required (hard cap; drop oldest, O(1)).
• Does not require Metrics.
• Set includeSnapshot: false to store only type + timestamp.

Overflow

const timeline = createTimelineApi(lifecycle, {
  maxEvents: 200,
  onOverflow: (dropped) => console.debug("dropped", dropped.type),
});

onOverflow fires once per entry evicted when the buffer is full — useful for detecting an undersized maxEvents in development.

format() options

timeline.format({ locale: "en-GB", timeZone: "UTC" });

Option	Type	Default
locale	string	Runtime default locale
timeZone	string	Runtime default time zone

Both are passed straight through to Date.prototype.toLocaleTimeString() for each entry.

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